The Monitor/Loader (M/L) is a resident firmware that is present on all Tibbo devices.
The M/L is launched every time a Tibbo device is powered up, reboots, or released from reset. When happens next depends on whether the MD button is pressed at the moment the M/L starts running:
If the MD button is not pressed, the M/L verifies the sanity of and launches Tibbo OS (TiOS) — the main firmware powering our Tibbo BASIC/C programmable devices (in its turn, TiOS then verifies and launches your compiled Tibbo BASIC/C app, provided that the app was compiled for release).
If the MD button is pressed, the M/L enters the firmware update mode. TiOS, as well as Tibbo BASIC/C app's binary can be updated in this mode. If the WA2000 Wi-Fi/BLE add-on module is present, the M/L can even update the internal firmware of the WA2000. For more information see Update Modes.
The M/L makes extensive use of two standard green and red status LEDs found on all Tibbo devices. Observe the patterns displayed by these LEDs to see what your Tibbo device is doing, or what error condition was detected.
TiOS (and Tibbo BASIC/C app) updates performed via the M/L should not be confused with TiOS (and Tibbo BASIC/C app) uploads from within TiOS itself. The difference here is that in order to update TiOS from within TiOS your device must already be running a healthy TiOS firmware. If your device is "bricked" (for example, because a wrong firmware file was uploaded into it), then the only way to "unbrick" it is by using the update function of the M/L.